The Clinical Core will serve two principle missions for the overall SPORE project. First it will provide an active and delineated collaboration with each principle and developmental project aimed at defining experiments that would lead to the design of Phase I and Il clinical studies regardless of the project's timeline to clinical application. Second, it is designed as a comprehensive resource for clinical trials and is specially tailored to therapies for breast cancer emerging from the laboratory and translational programs.. The first goal is to link key personnel in the Clinical Core to individual scientific projects in order to incorporate clinical objectives at all stages of project development. Core members will participate in laboratory meetings pertaining to their assigned project and will lead meetings and planning sessions to formulate clinical development strategies. Members will utilize ongoing collaborations with biotechnology and pharmaceutical industry partners as well as local and national cancer cooperative groups in order to assist individual projects in obtaining IND's and licensure and in the design and implementation of clinical trials. The second goal is accomplished by coordinating a multidisciplinary group of clinicians throughout the Bay Area committed to SPORE-related clinical trials. Current clinical activities and ongoing trials specifically include those that identify patients and set the procedural groundwork for SPORE projects as they approach the clinical trial stage. SPORE-related clinical trials through this Core will be supported by a research database and statistical support through the Epidemiology and Biostatistics Core. Institutional review, data management, and quality assurance will be operational at each clinical site.